1. Definitions and general information

1.1 Terminology problems

The choice of electrolytes and electrodes that can be used in supercapacitors is very wide, and research carried out over the last 30 years has already revealed a large number of possibilities. This has led to the emergence of specific terms, although the nomenclature is not yet perfectly stabilized. Since the introduction by the NEC Corporation of the name supercapacitor, translated here as supercapacitor, there has been frequent use in Anglo-Saxon literature of terms and acronyms such as ultracapacitor, double-layer capacitor (DLC), electric double-layer capacitor (EDLC), electrochemical double-layer capacitor (ECDL) or electrochemical supercapacitor. These names attempt to distinguish devices that use mainly electrostatic or both electrostatic and faradaic...